It seems acceptable to complete a Single Engine IR and then get converted by one of the North Sea three to a twin type for their ops.
Since Bristow's are the only ones in the UK with a single engine IR course that's one way to go. I haven't heard of the non-Bristow companies having a problem with Bristow's IR; I don't see why they should, from what I hear it's a good course.
Having said that, cost-wise, the various twin courses around are not much different in price and you come out with a twin rating (the Bristow course does not include a 206 rating).
As I'm looking at these options right now, I do feel rather nervous at putting down so much money simply to be able to apply for a job...I imagine the bank will feel the same way!
BG